Underwater breathing apparatus



April 1965 w. F. MITCHELL ETAL 3,179,118

UNDERWATER BREATHING APPARATUS Filed April 16, 1962 I 5 Sheets-Sheet 2 INVENTORS Wa//ace /I M/ /Cfi9// Samue/ M Dav/$011, 65w awf/g za/gg A TTORNE YS April 20, 1965 w. F. MITCHELL ETAL 3,179,118

UNDERWATER BREATHING APPARATUS Filed April 16, 1962 3 ;Sheets-Sh-eet 3 Samae/MDmnlsan,

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A ORNE YS United States Patent 3,179,118 UNDERWATER BREATHKNG APPARATUS Wallace F. Mitchell, Arlington Heights, and damuel M.

Davison, J12, Skolsie, 111., assignors to Dacor Corporation, Evanstcn, ill., a corporation of Illinois Filed Apr. 16, 1962, Ser. No. 137,822 (Jlairns. (Cl. 137-63) The present invention generally relates to underwater breathing apparatus, and it more particularly relates to self-contained underwater breathing apparatus of the type including two separate pressure regulating stages in which a single, flexible hose is connected between a first stage regulator and a second stage regulator, the second stage regulator having incorporated directly therein a mouthpiece through which the user may breathe.

Self-contained underwater breathing devices of the single hose type preferably employ a relatively compact second stage regulator for the reason that it is generally supported directly on the face of the diver. Hence, it should be light in weight and small in over-all size so as to avoid undue obstruction of the divers visibility.

In self-contained underwater breathing dveices of the two-stage type, the first stage regulator is commonly attached directly to the air supply tank and reduces the air pressure to a value appreciably less than that within the tank. The outlet pressure from the first stage is generally adjusted to a pressure of approximately 110 p.s.i. Since the second stage regulator is supported by the head of the diver, it is connected to the first stage regulator by means of a flexible coupling in the form of a rubber hose. The second stage regulator performs two functions. One, it further reduces the air pressure to approximately that of the external pressure on the diver which pressure varies with depth, and two, it functions as a valve to control the admittance of air to the mouthpiece. Accordingly, the second stage regulator should permit normal breathing by the diver and it must be compact in design and extremely reliable in operation since any jamming thereof could be fatal.

An object of the present invention is to provide new and improved underwater breathing apparatus of the two stage single hose type.

Another object of the present invention is to provide a new and improved regulating valve for use in a two-stage pressure regulator.

Still another object of the present invention is to provide a new and improved pressure regulating valve for use in self-contained underwater breathing apparatus.

A further object of the present invention is to provide a new and improved valve actuating linkage for use in a presure regulator.

Further objects and advantages and a better understanding of the present invention may be had by reference to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a sectional view of a second stage regulator embodying the present invention, which regulator is particularly adapted for use in two-stage, single hose pressure regulating system;

FIG. '2 is an enlarged plan view of a force multiplying valve actuating linkage mechanism incorporated in the pressure regulating device of FIG. 1;

FIG. 3 is a front view of the pressure regulating device of FIG. 1;

FIG. 4 is a side view of the pressure regulating device of FIG. 1;

FIG. 5 is a view similar to FIG. 3 with certain portions of the regulator removed to illustrate certain internal parts thereof;

FIG. 6 is a partially sectioned View of a first stage regulator used in combination with the regulating device of FIG. 1; and

PEG. 7 is a crosssectional view of the pressure regulating device of FIG. 6 taken along the line 77 assumi-ng the entire device to be shown in FIG. 6.

Refering now to the drawings, there is shown in FIG. 1 a pressure regulating device *lti having a. mouthpiece 12 fixedly attached thereto for supplying air from the regulater it to the mouth of the user. Air is supplied under pressure to the regulator 1th through a flexible hose 14 which is connected between the regulator 11), as best shown in FIG. 1, and a first stage pressure regulator 16, as best shown in FIG. 6 and briefly described herein after. he regulator 16, which is adapted to be connected directly to a conventional air supply tank (not shown) which contains a supply of air at a pressure of the order of 2,000 p.s.i., reduces the air pressure to a value of approximately p.s.i. and supplies it at such reduced pressure to the hose id. The regulator -10 further reduces this pressure to that of the surrounding water and supplies it to the mouthpiece -12 in accordance with the needs of the diver.

The first stage regulating valve 16, as best shown in FIGS. 6 and 7, comprises as its principal element, a high-pressure body 20, which is generally tubular and which includes a depending tubular portion 21 having a cylindrical recess 22 therein terminating at a transverse wall 2-3. A conventional yoke member 24 is rotatably secured to the body 2% by means of a yoke nut 25 which is threadedly received on the boss 21. A dust cap 26 is loosely secured to the yoke 24- by means of a ring 27 and may be held in place over the boss =21 against the external face of the yoke nut 25 by means of a thumb screw -29 which is threadedly received in the yoke 24. L1 use, the dust cap 26 is removed from the boss 21 by loosening the thumb screw 29, and the valve 16 is then assembled to the outlet coupling of the air supply tank. The thumb screw 29 is provided for attaching and holding the tank coupling tightly against and over the boss 21, thereby to prevent leakage of air at the coupling between the tank and the regulator =16.

Air at tank pressure thus enters the regulator 16 through the recess 22 and passes through a fine mesh filter disc 32 to the lower side of a high pressure valve member '33 which, :as best shown in FIG. 7. is substantially square in cross section and axially slidable in the recess 22. A coil spring 34 is operatively received in a cylindrical recess 35 in the valve member 33 and seats against the filter disc 32. Spunious disassembly of this portion of the regulator is prevented by means of a snap ring 36 which is received in a suit-able annular groove in the wall of the recess 22.

The wall 2 3 is provided with an axial bore 37 having a counterbore 38 at the lower end thereof surrounded by a depending annular valve seat 39. An annular resilient ring 40 is supported in a complementary groove in the upper face of the valve member 33 for sealing engagement with the valve seat 3h. It may be seen that air pressure in the tank thus tends to hold the ring 40 tightly against the valve seat 39.

The valve body 29 is provided at its upper end with a cylindrical recess 43 having an internally threaded counterbore 44. A circular diaphragm :5 rests on an upwardly facing shoulder provided between the recess 43 and the counterbore 44-, and a generally tubular clamping sleeve 46 holds the diaphragm tightly against the shoulder to eifect a hermetically tight seal between the edges of the diaphragm i5 and the body 2 6. A hex-head screw 48 loosely extends through a central aperture in the diaphragm i5 and through an aperture in a washer 49. The washer 4? is compressed against the diaphragm 45 which is, in turn, compressed against the head of the screw 48 by a; means of a lock nut. Accordingly, a pressure-tight chamher is provided in the portion of the recess 43 below the diaphragm 45 and this chamber is coupled by means of a conduit 52 and a threaded hole 53 to the coupling 54 of the hose 14. A valve actuating push rod '5 very loosely extends through the bore 37 and is interposed between the valve member 33 and the screw 43 for moving the valve member 33 relative to the seat 39 in accordance with the pressure dififerential across the diaphragm 45. A pressure adjusting cap 56 is threadedly received in the upper end of the sleeve and a coil spring 57 centrally located on the nut is compressed between the cap 6 and the nut to exert an adjustable bias force on the diaphragm 45. A screwdriver slot 53 is provided in the top surface of the cap 556 for accommodating the head of a screwdriver used in adjusting the output pressure of the regulator 16. The sleeve as is provided with one or more apertures 59 whereby the upper surface of the diaphragm i5 is at the ambient pressure which depends upon the depth of the diver in the water.

Referring now to FlG. 1, air at a pressure whose value is determined by setting of the cap 56 is thus applied Via thehose i lto the regulator 16. As shown, the hose 34 is removably secured to a tubular member es by means of a conventional swivel coupling as threadedly receiver in a counterbore er in the member 65. An annular sealing gasket d8 supported in a suitable groove 69 in the coupling member 66 prevents leakage of air.

As best shown in Flu. 1, the member includes an axial bore '72 therein surrounded by a sharpedgcd annular valve seat 73. A counterbore in the member 65 provides a generally cylindrical chamber partially surrounding the valve seat 73. T he member 65 has an external thread '7! for removable attachment thereof to a enerally tubular coupling member which is integral with the regulator housing.

The coupling member '78 includes an end wall having an elongated centrally disposed tubular bearing portion 32 provided with an axially disposed bore 83 functioning as a guide for a valve rod 84 of a valve member 85. The valve member 35' includes, in addition to the plunger 84, which is integral therewith, a cylindrical end portion hava tili/ ing a cylindrical recess therein for receiving a resilient disc 86 tightly supported therein for controlled seating engagement against the annular valve seat '73. Air which passes between the valve member and the seat 73 is coupled into the housing 39 via a plurality of drilled holes 88 in the end wall of the coupling member '78.

In order to axially move the valve member 85 in accordance with the air needs of the diver, the valve rod 34 extends into a chamber 9 which is defined by the cup-like main housing member 8t) and an imperforate flexible diaphragm 91 which is sealably secured over the top of the housing Stl. The diaphragm 91 is protected from damage by means of a cover 92. The upper end of the housing till, as viewed in FIG. 1, includes an outwardly directed annular flange 93 having an up-turned annular lip 4 thereon providing a ledge or rabbet in which the enlarged peripheral portion 95 of the diaphragm 91 is supported. The cover 92 includes an annular flange as which rests on the diaphragm flange portion 95 and the entire assembly is held together by means of a plurality of nuts 97 and bolts 98, best shown in FIGS. 3 and 4. The cap 92 includes a plurality of peripherally disposed holes 99 which connect the upper side of the diaphragm 91 with thewater so that the diaphragm 91 experiences on its upper surface a pressure substantially equal to that on the diver.

The housing member 8% is generally cup-shaped and has a hat, circular bottom wall 162 and an outwardly tapered side wall which is generally frusto-conical. An elongated aperture 193 is provided in the side of the housing 8n and connected via a similarly shaped tubular connector M4 to a rubber mouthpiece 12, which is tightly fitted over the connector 1M and secured thereto by means of a suitable clamping ring 1%.

in or er to permit expulsion of gases from the chamber 9% during exhalation of the diver, an exhaust conduit 107 is provided in the wall of the housing 8% opposite to the breatl ing aperture A conventional check valve 1% formed of a flexible rubber disc or the like is mounted across the conduit M7. The other end of the conduit M97 is connected to an exhaust manifold H39. As best shown in FIGS. 3, 4 and 5, the manifold 1599 includes a central tubular hub portion lltl which is tightly fitted over the conduit ill? and secured thereto by means of a suitable ring clamp 112. A pair of rearwardly extending exhaust pipes 113 and 114 which communicate with the bore throu h the connector M 7 radiate rearwardly from the hub In order to control the operation of the inlet valve 85 in response to the pressure differential across the diaphragm 91, there is provided in accordance with an important feature of this invention, a multiple leverage linltage lllti operativcly connected between the lower face of the diaphragm 91 and the hemispherical end of the valve rod 34. Movement of the diaphragm towards the bottom of the regulator housing, which movement occurs as a result of a relative reduction of the pressure within the chamber 90, permits the valve 85 to open under pressure of the air being supplied th reto through the hose 14.

As best shown in RES. 1 and 2, the multiple lever assembly 115 comprises a lever support bracket ill? which is generally in the form of a channel having a flat bottom wall H8 and a pair of pstanding side walls 119 and lib. The bracket is secured to the housing member till by means of a pair of grooves 122 and 123. As shown, the screws 122 and L3 also attach a neck strap bracket 3124 to the housing 36. The lever support bracket 11? includes a pair of upstanding ears 126 and 127, formed by extensions of the side walls 11) and 120, which, in conjunction with a pivot rod 123 secured therebetween in suitable apertures, provide a trunnion support for a lever member 134?. The member 138 has a pair of upstanding side walls 13-1 and 132 pivotably secured to the rod 123. As shown, the lever 13% is generally channel shaped to provide increased strength and the upper ends of the side walls, as viewed in FIG. 1, are identical and each provided with a smoothly curved diaphragm engaging surface 1'34. As shown, the diaphragm 91 includes a centrally disposed, circular metallic disc 1156 thereby to provide a smooth, downwardly facing surface across which the lever surfaces 134 are adapted to travel. =Connected between the Walls 131 and 132 of the lever 139 is a flat wall portion 137 from which depends an actuating button 133 having an extremely smooth, hemispherically shaped end 139 for engaging a lever member Ml. Pr "erabl the surface 139 is formed of a hard, self-lubricating, smooth, wear-resistant material such, for example, as tetrailuoroethylene. The lever member 141 has a fiat wall portion 142 and a pair of depending side walls lid?) and l tt which are suitably apertured at their ends to loosely receive a pivot rod 145' which is secured in a pair of aligned apertures in upstanding ears 14-6 and 147 formed by extensions of the side walls of the bracket 113. The lever 141 also includes, at the left-hand end thereof as viewed in PEG. 1, an integral, upstanding tab portion 14$ located along the longitudinal axis of the valve rod Accordingly, oscillation of the lever 141 above the pivot rod 145 moves the tab 148- along the axis of the rod 8 whereby clockwise movement of the lever 141 permits the valve to open an increasingly greater amount, while counterclockwise movement of the lever 141 moves the inlet valve 85 into a closed position.

In order to bias the inlet valve 85 into a closed position so that air is supplied to the chamber S ll only when the pressure tl erein is less than the pressure on the outer surface of the diaphragm 91, a spring 15% is loosely coiled about the rod 145 and includes a pair of end portions 151 and 152 which seat against the top surface of the wall 118. The spring ft further comprises a central, loop portion 153 which presses against the bottom wall of the lever 141. In FIG. 2, the spring 150 is illustrated in its unstressed condition. Accordingly, when the lever 141 is rotated clockwise, as viewed in FIG. 1, the spring 15% is compressed and urges the lever 141 in a counterclockwise direction, thereby to bias the valve member 85 into a closed position. The spring 156 is selected to have a tension sufficient to overcome the opening force exerted on the inlet valve 85 by the air pressure in the hose 14. However, a close balance of the spring pressure and the air pressure is required so that there will be no leakage of air when the system is not in use, and yet permit the inlet valve 85 to open and admit air to the mouthpiece 12 in response to a small pressure differential across the diaphragm 91.

In operation, when the pressure within the chamber 90 is less than the pressure on the outer surface of the diaphragm it, the diaphragm 92 moves into the chamber 90 thereby to pivot the lever 132 in a counterclockwise direction. The button 138 is, in turn, moved downwardly against the lever 141 to pivot it clockwise and move the valve operating tab 148 away from the end of the valve rod 84. Air pressure within the hose 14 may thus push the valve 85 away from the seat '73 to admit air into the chamber 96 and thus into the mouthpiece 12. During exhalation by the diver, the pressure in the chamber 94 normally increases, thereby to move the diaphragm 91 upwardly. The spring 150 thus pivots the lever 141 in a counterclockwise direction to close the inlet valve 85.

In order to permit manual opening of the valve 35, for example, to expel water from the chamber 96 past the exhaust valve member 108, there is provided a generally cylindrical button-type actuator 156 which is slidably mounted in a necked-down aperture 157 at the center of the cap 92. A coil spring 158 surrounds the button 156 and is slightly compressed between the upper surface of the cap 92 and a sli htly enlarged circular head portion 15 on the button 156. A washer 160 is secured to the bottom of the button 156 to hold it in place. It may be seen that depression of the button 156 forces the diaphragm 91 downwardly, thereby to manually move the valve actuating tab 148 away from the valve rod 84. Air may thus enter the chamber 90 from the hose 14.

While the present invention has been described in connection with a particular embodiment thereof, it will be understood that those skilled in the art may make many changes and modifications without departing from the true spirit and scope of this invention. Therefore, it is intended that the appended claims cover all such changes and modifications as fall within the true scope and teachings of the present invention.

I claim:

1. In a pressure regulator for use in self-contained underwater breathing apparatus, a unitary sub-assembly attachable to and removable from associated structure as a unit and comprising a single channel-shaped bracket having upstanding side walls, a first pivot rod supported in said walls at one end of said bracket, a second pivot rod supported in said walls at the other end of said bracket, a first lever pivotally supported on said first pivot rod between said walls and extending toward said other end of said bracket, a second lever pivotally supported on said second pivot rod between said walls and partially overlying said first lever, a finger depending from said second lever into engagement with said first lever between said first pivot rod and said other end of said bracket, and a spring having a central portion coiled around said first pivot rod and having end portions compressed between said bracket and said first lever to resiliently urge said first lever against said depending finger on said second lever, said first lever having an extending portion in proximity to said first pivot rod for operative engagement with a movable valve member.

2. The invention as set forth in claim 1 wherein said second lever is generally channel-shaped and has spaced, parallel side walls formed with free outer arcuate edges for engaging a diaphragm.

3. In underwater breathing apparatus, the combination of a housing, a diaphragm disposed across a portion of said housing to define a pressure chamber therein, a breather tube connected to said chamber, a linkage mechanism mounted in said chamber in operative engagement with said dia hragm, said mechanism including a valve operating portion pivotally movable in response to movement of said diaphragm relative to said chamber, a generally tubular coupling member secured to and extending through said housing into said chamber, said coupling member having an elongated centrally disposed bore, a valve member having a valve rod extending through said bore into said chamber for engagement by said valve operating portion, a tubular housing member removably secured to said coupling member having a central aperture therethrough, an annular valve seat surrounding said aperture and facing toward said valve member, said tubular housing member having a counterbore wholly receiving said valve seat therein and means for supplying air under pressure to said tubular housing member on the side of said aperture opposite to said valve member.

4. A pressure regulator comprising a circular cup-like housing having a generally frusto-conical side wall tapering inwardly toward the bottom, a breather tube opening into said housing, an exhaling conduit opening into said housing, an imperforate, flexible diaphragm covering the open top of said housing to provide a pressurizable chamber in said housing, a tubular connector on said housing, an apertured wall interposed between said connector and said chamber, said apertured wall having an axially directed sleeve therein, a tubular valve seat housing member secured to said connector in substantial alignment there with and having a bore and counterbore aligned with said sleeve and a valve seat wholly within said counterbore, a piston valve member having an axial rod portion slidably mounted in said sleeve, and a valve operating linkage connected between said diaphragm and an end of said rod extending into said chamber, said linkage including spring means urging said rod out of said chamber into a valve seating position and force multiplying means between said diaphragm and said rod.

5. In underwater breathing apparatus, the combination of a housing and a diaphragm defining a pressurizable chamber, a tubular coupling member extending through said housing into said chamber, a generally tubular inlet valve threadedly connected to said coupling member, said inlet valve including a body portion having a central bore surrounded by an annular valve seat and a pair of counterbores at the respective ends thereof, one of said counterbores wholly receiving said valve seat therein, a valve member having a seat engaging portion and a valve rod portion, said valve member being disposed in said body portion for movement against and away from said valve seat, said coupling member having an axial guide bore in which said valve rod is slidably disposed, said valve rod extending partly into said chamber when said valve member sealably engages said valve seat and means disposed in said housing for operatively connecting said diaphragm to said valve rod for operating said valve in response to movement of said diaphragm.

References Cited by the Examiner UNITED STATES PATENTS 1,618,671 2/27 Pick 137-63 1,621,498 3/27 Drager 137-63 2,318,827 5/43 Yant 13764 2,557,187 6/51 Hanssen 137-505.46

(@ther references on following page) I? UNITED STATES PATENTS Cupp 128-142 Gagnan 128-142 Galeazzi 128-l42 Rose 128-142 Fay 137-64 Pitt 137-64 Mitchell 137-64 X Novelli 137-64 XR Cousteau 137-63 32 FOREIGN PATENTS 10/36 Great Britain.

OTHER REFERENCES IS-ADOR NEIL, Primary Examiner. 10 M. CARY NELSON, Examiner. 

1. IN A PRESSURE REGULATOR FOR USE IN SELF-CONTAINED UNDERWATER BREATHING APPARATUS, A UNITARY SUB-ASSEMBLY ATTACHABLE TO AND REMOVABLE FROM ASSOCIATED STRUCTURE AS A UNIT AND COMPRISING A SINGLE CHANNEL-SHAPED BRACKET HAVING UPSTANDING SIDE WALLS, A FIRST PIVOT ROD SUPPORTED IN SAID WALLS AT ONE END OF SAID BRACKET, A SECOND PIVOT ROD SUPPORTED IN SAID WALLS AT THE OTHER END OF SAID BRACKET, A FIRST LEVER PIVOTALLY SUPPORTED ON SAID FIRST PIVOT ROD BETWEEN SAID WALLS AND EXTENDING TOWARD SAID OTHER END OF SAID BRACKET, A SECOND LEVER PIVOTALLY SUPPORTED ON SAID SECOND PIVOT ROD BETWEEN SAID WALLS AND PARTIALLY OVERLYING SAID FIRST LEVER, A FINGER DEPENDING FROM SAID SECOND LEVER INTO ENGAGEMENT WITH SAID FIRST LEVER BETWEEN SAID FIRST PIVOT ROD AND SAID OTHER END OF SAID BRACKET, AND A SPRING HAVING A CENTRAL PORTION COILED AROUND SAID FIRST PIVOT ROD AND HAVING END PORTIONS COMPRESSED BETWEEN SAID BRACKETS AND SAID FIRST LEVER TO RESILIENTLY URGE SAID FIRST LEVER AGAINST SAID DEPENDING FINGER ON SAID SECOND LEVER, SAID FIRST LEVER HAVING AN EXTENDING PORTION IN PROXIMITY TO SAID FIRST PIVOT ROD FOR OPERATIVE ENGAGEMENT WITH A MOVABLE VALVE MEMBER. 